Launch outlook hidden on windows startup

Question

Windows startup -> launches my application -> this application should launch outlook in hidden mode (not in taskbar, just outlook.exe running in the back / tray)

Tried a bunch of workarounds with different Sleep waits (I know, ain't a good practice), but nothing that really ensures that outlook will be launched hidden no matter the timing. - The code belows has every workaround imaginable to me, nothing worked bulletproof.

Private Sub OutlookCheck()
        Dim isOpen As Boolean = False
        Threading.Thread.Sleep(6000)
        For Each p As Process In Process.GetProcessesByName("outlook")
            If p.ProcessName.Contains("OUTLOOK") Then
                isOpen = True
            End If
        Next

        If Not isOpen Then
            Try
                PrintAndLog("Outlook not running yet")
                Threading.Thread.Sleep(6000)
                StartOutlookHidden()
            Catch ex As Exception
                ErrMsg(ex.Message)
            End Try
        Else
            PrintAndLog("Outlook already running, trying to close")
            For Each p As Process In Process.GetProcessesByName("outlook")
                If p.ProcessName.Contains("OUTLOOK") Then
                    p.Kill()
                    PrintAndLog("Outlook process with ID: " & p.Id & " found and killed. Starting routine for hidden Outlook")
                    Exit For
                End If
            Next
            Threading.Thread.Sleep(6000)
            StartOutlookHidden()
        End If
    End Sub

    Public outlookhWnd As IntPtr
    Private outlookHideTicks As Short = 5
    Private Sub StartOutlookHidden()
        Try
            Using regKey As Microsoft.Win32.RegistryKey = Microsoft.Win32.Registry.CurrentUser.OpenSubKey("Software\Microsoft\Office\16.0\Outlook\Preferences", True)
                regKey.SetValue("MinToTray", 1, Microsoft.Win32.RegistryValueKind.DWord)
                regKey.Close()
            End Using
        Catch ex As Exception
            ErrMsg(ex.Message)
        End Try

        Dim pset As ProcessStartInfo = New ProcessStartInfo
        With pset
            .FileName = "outlook.exe"
            .WindowStyle = ProcessWindowStyle.Minimized
            .CreateNoWindow = True
        End With
        Using p As Process = New Process
            With p
                .StartInfo = pset
                .Start()
            End With
            Threading.Thread.Sleep(6000) 'Wait for outlook to open
            outlookhWnd = p.MainWindowHandle
            ShowWindow(p.MainWindowHandle, SHOW_WINDOW.SW_HIDE)
        End Using

        Dim i As Threading.Thread = New Threading.Thread(Sub() AddidtionalHide())
        i.SetApartmentState(Threading.ApartmentState.STA)
        i.Start()

        PrintAndLog("Hidden Outlook started")
    End Sub

    Private Sub AddidtionalHide()
        ShowWindow(outlookhWnd, SHOW_WINDOW.SW_HIDE)
        Threading.Thread.Sleep(2000)

        For Each p As Process In Process.GetProcessesByName("outlook")
            ShowWindow(p.MainWindowHandle, SHOW_WINDOW.SW_HIDE)
        Next

        outlookHideTicks -= 1
        If outlookHideTicks >= 1 Then
            AddidtionalHide()
        End If
    End Sub

I want outlook to open along with my application, but hidden in the background. Since outlook doesn't bother about processproperties and the initial window handle is only used when it opens the mainwindow(usually inbox) and not before, I find it hard to get a code that'll work on all machines.

Answer 1

Simply create an instance of the Outlook.Application object and keep a reference to it.